Metabolomics-Based Approach for Coffee Beverage Improvement in the Context of Processing, Brewing Methods, and Quality Attributes

Abstract

Coffee is a worldwide beverage of increasing consumption, owing to its unique flavor and several health benefits. Metabolites of coffee are numerous and could be classified on various bases, of which some are endogenous to coffee seeds, i.e., alkaloids, diterpenes, sugars, and amino acids, while others are generated during coffee processing, for example during roasting and brewing, such as furans, pyrazines, and melanoidins. As a beverage, it provides various distinct flavors, i.e., sourness, bitterness, and an astringent taste attributed to the presence of carboxylic acids, alkaloids, and chlorogenic acids. To resolve such a complex chemical makeup and to relate chemical composition to coffee effects, large-scale metabolomics technologies are being increasingly reported in the literature for proof of coffee quality and efficacy. This review summarizes the applications of various mass spectrometry (MS)- and nuclear magnetic resonance (NMR)-based metabolomics technologies in determining the impact of coffee breeding, origin, roasting, and brewing on coffee chemical composition, and considers this in relation to quality control (QC) determination, for example, by classifying defected and non-defected seeds or detecting the adulteration of raw materials. Resolving the coffee metabolome can aid future attempts to yield coffee seeds of desirable traits and best flavor types.

Keywords: Coffea arabica; Coffea canephora/robusta; adulteration; brewing; coffee; metabolomics; quality control.

Figure 1

Metabolic class determinants affected by coffee breeding can be determined by different metabolomics approaches.

Figure 2

Metabolic markers indicative of roasting degree of coffee as determined by different metabolomic approaches. Green and red arrows indicate increase or decrease upon roasting, respectively.

Figure 3

List of the different brewing factors contributing to volatile and non-volatile metabolic profiles of coffee brews. The metabolites markedly increased with specific brewing methods are mentioned based on the detection method used.